Hero Switch
by ninja.universe
Summary: Peter Parker was finally juggling school and Spiderman but he makes a mistake that spirals everything out of his control. An experiment gone wrong forces him to switch bodies with his mentor Tony Freaking Stark!
1. Deceiving Myself

Chapter 1

Tony Stark was working in his lab with rock music blasting on a high volume. It was the perfect chance for Peter Parker to sneak in on the ceiling. Luckily the lab wasn't locked down and Peter crawled through the doorway while on the ceiling. Upside above Tony, he couldn't tell what he was working on and he didn't wait to find out. This was his chance.

Peter lowered himself with his webs and stopped himself in front of the billionaire's face. "Boo!"

Tony flinched and he squeezed the dropper in his hand. The chemical in the dropper spilled into his experiment and onto the work table.

Stark set the dropper down to clutch his arc reactor in shock. "Jesus Pete... this is why I have gray hairs. FRIDAY, music."

The music in the lab shut off. Peter lowered himself to the table and he crouched on the other side of his bubbling concoction. He was wearing his Spiderman suit with his mask in his hand. He smiled and laughed lightly. "Sorry Mr. Stark! Didn't mean to scare you that bad. So what does that make the score? Me 3 and you 2?"

Tony smirked and stood from his stool. "That's not how I remembered it. Pretty sure it's me 3 and you now have 2." His eyes drifted to his experiment and Peter followed his eyes.

"I'm so sorry Mr. Stark! Was that important?" Peter asked pointing to the foaming liquid. Tony flicked some of his hovering holograms away.

Tony smiled in reassurance to the teen. "Nope just a test. Nothing to worry-"

He was interrupted by a puff of smoke blowing up into their faces. Tony grabbed a rag and tried to waft it away.

Tony coughed, "I wouldn't inhale that. Dummy clean this up and if you break anything I'm going to scrap you and send you to some engineering college."

Peter hopped down from the table and coughed into his elbow. Tony stepped away from the experiment and gripped the table to steady himself.

"Are you ok, Mr. Stark?" Peter asked as he gripped the table feeling slightly dizzy.

Tony stood up straight and sigh, "Kid remember what we talked about? Stop with that 'Mr. Stark' bullshit." When he said his name he mimicked Peter. Tony coughed out a laugh. "Isn't it a school night or something? What are you doing here so late?"

"I was patrolling in the area and figured I would stop by. I thought you missed seeing me around." Peter explained and walked around the table to stand in front of Tony.

"Pete, you were here yesterday."

"Close. I was here Friday."

Tony raised an eyebrow, "What day is it?"

"Sunday"

"So it is a school night."

"Yea but I wanted to see you." Peter answered as he looked to the ground.

Tony patted his shoulder, "Relax kid. You're not in trouble, I'm glad you stopped by. You always get me to take a break from my work."

Peter looked nervously between Tony and the smoking experiment over his shoulder. "Are you sure you're not mad about that?"

Tony turned over his shoulder and saw Dummy using the fire extinguisher, which did very little to stop the smoking. "It was just for fun. I have all the data written down if you're wondering. It's not going to kill me to recreate it."

Peter's shoulders slumped to a more relaxed position. "So you up for a movie?" He asked with a grin.

Tony smiled and guided Peter out of the lab. "I haven't forgotten that it's a school night. FRIDAY shut the lab down."

Peter and Tony went to the living quarters in the Avengers Tower. They talked and ate dinner together. Tony tried to convince Peter to let Happy drive him home but Peter insisted on leaving as Spiderman. It wasn't long after for Peter to leave because of Stark's persistence and a growing headache.

Peter swung home, increasingly wishing he had taken Tony's offer and let Happy drive him. Whatever Tony's experiment was, it made him feel sick to have inhaled the chemicals even for a split second. He felt dizzy and like throwing up, plus the headache. Once he made it home, he quickly slipped into his room and changed into his pajamas.

The time was 10:49 pm and if Peter knew his Aunt May, she would already be asleep. He set his alarm and the dizziness became unbearable and he almost threw up where he stood. He was tempted to call Tony and ask if Bruce could whip up some medication for his fast metabolism. He decided against it because he was too exhausted to think about staring at his phone screen and having a conversation.

It only took a few moments after he laid in bed to fall into a dreamless sleep.

* * *

Peter began to stir feeling hot under his silk sheets. Silk... That wasn't right. Peter became more awake from his confused thoughts. He opened his eyes to see a different environment than he was expecting. '_Avengers Tower?'_

Maybe he was sicker than he thought and he imagined going home last night. Aunt May would kill him for spending the night at Stark's on a school night. '_School... shit.'_

Peter removed the sheets tangling his body but the movement was so different. He still felt sick. The sheets were removed and he sat there and contemplating even going to school.

"FRIDAY?" Peter asked but stopped dead in his tracks in fear. What the hell... Was Tony in the room too? He looked around confused and freaked out.

'_Wait a minute.. I'm in Tony's room! Maybe he was sick too and decided to was best to keep us together? But where was he?'_

"FRIDAY? What time is it?" Peter was freaking out. He was hearing Tony talk at the same time as him but he didn't see him anywhere.

"It is approximately 6:47 am. Shall I inform Pepper Potts that you are awake?" FRIDAY responded and Peter stood from the bed shakily. He felt weak and dizzy so he grabbed the bedside table to stead himself. Eventually he put more and more weight on the nightstand. The small table tipped and fell over bringing Peter with it.

The crash was loud and Peter was internally screaming. He stayed on the ground and his chest ached terribly. He reached up to his chest and felt a foreign object. Peter held his breath and he looked down as far as he could. He was wearing jeans and an AC/DC t-shirt but there was something underneath the fabric. An Arc Reactor is what Peter saw and he nearly threw up in shock.

"Ms. Potts has been informed of your distress." Friday announced and Peter only panicked more.

"Shit. Shit. Shit. Fuck." Peter cursed and even sounded like Tony Stark. He sat up and the sick feeling came back full force. His arms shook and he fell back to the ground. One hand gripped the Arc Reactor and the other was digging into his temple.

"Tony?! Oh my god!" Peter heard the fast paced click of her heels come into the room as she raced to his side. He felt extremely uncomfortable wearing the skin of Tony Stark and being in the room with his fiancée. He squeezed his eyes shut in pain and because he was afraid to look at her. "Are you okay?"

Peter had to think quick. What is a good response? "No" '_Wow great job Peter Parker! They'll never figure you out now!'_

Pepper she crouched next to him. "What's wrong?" She asked and rested a hand on Peter's arm. He flinched violently and she removed her hand.

He contemplated telling her but cons out weigh the pros. "I might be sick..." '_Lame_' Peter thought. "I think I exposed myself to something harmful in the lab."

Pepper sighed and Peter could feel a scolding coming, "I keep telling you, you're spending too much time in the lab. But that doesn't stop you. Come on let's get you back in bed." She put her hands under Peter's back to help him up.

She helped him stand but his legs gave out on him and Pepper held him up. She lowered him into the bed and covered him with the silk sheets.

Peter groaned and threw the sheets off. "No sheets." '_Think Peter... unlock your inner Stark.'_ "Pep-per this might be serious. The kid was here last night and he was exposed to the same thing. I'm going to send Happy to get him."

Pepper rested a hand on Peter's forearm and he didn't flinched from her touch this time. "Tony, it's a school day, Peter has his own responsibilities."

"I have a feeling he won't be at school today if he is feeling the same way I am." Peter insisted.

"At least wait till his school gets out to drag him away. I have to go to a meeting in Malibu so I'll be gone for a few days. Are you sure you can handle yourself?"

Peter looked her in the eyes, "I'm Tony Stark, of course I'll be fine." Peter was still internally screaming and panicking.

Pepper giggled, she leaned forward and kissed his forehead. "Get some rest and you better not be in the lab when I get back."

Pepper left the room and Peter sighed in relief. He almost caved and told her but he was worried she'd bring S.H.I.E.L.D. into this.

Peter looked to the mess he made next to the bed and his eyes landed on a Stark phone. He almost lunged off the bed to grab it. Peter carefully got up and grabbed the phone making sure not to fall over or alert Pepper. He knew exactly what he had to do. He opened the phone to have multiple messages from a contact named Spider Kid.

* * *

After Peter left, Tony went straight to his penthouse. He didn't want to admit it to Peter but he was not feeling well. He didn't change clothes, instead he quietly got into bed next to Pepper. He was glad to finally get some rest even if it was from not feeling well.

You can imagine how upset he was to be woken up by an alarm. Tony grimaced at the blaring alarm and groaned into his pillow that smelled like sweat.

"FRIDAY turn it off." Tony mumbled but the sound continued. He groaned again and sat up. "Ok you got me, I'm up now turn it off."

The alarm continued to deafen Tony. He gave up on the AI and opened his eyes. "What the fuck.."

Tony quickly grabbed the phone responsible for the alarm and he shut it off. He looked around the small room and he recognized it. '_Peter's room..'_

"Peter! Get up and get dressed! You're going to be late if you continue to let your alarm ring." A voice from the other side of the door shouted. '_Aunt May..._'

The world to Tony was loud and the stream of light coming through the curtains was blinding. Tony collapsed back into the bed feeling completely overwhelmed. He had a crushing headache and his stomach was against his body.

Tony grabbed the phone and looked to the time. 6:20 am. He unlocked the phone with Peter's fingerprint and opened messages. He found his own contact labeled Mr. Stark.

Tony: We need to talk

Tony: Now

Tony: Don't do anything stupid

Tony thought it was necessary to add the last part. The handle of the door began to jiggle and Tony stuffed the phone under the pillow.

"Peter you're going to be late- You didn't even get out of bed?!" Aunt May saw Tony miserable in bed. She sat next to him. "What's wrong honey?"

Tony remembered that she doesn't know about Spiderman and decided to choose the safe option. "I don't feel so good."

Aunt May made a fist, "I swear that Stark internship is giving you ridiculous hours. You should be resting and enjoying high school."

"But I am enjoying high school! The Stark internship is a bonus! The hours are flexible but I always choose to go there." Tony argued and felt like he needed a conversation with Peter.

Aunt May placed a hand on his forehead and sighed, "You can stay home today but know that I'm not happy and if you come home late from the internship and ask to stay home, I'm not going to be so understanding. Got it?"

"Yes ma'am." Tony responded and she left closing the door gently. He sat up and threw off his blankets but dizziness made him freeze. Tony grabbed his head and hissed in pain.

Everything was loud and he was too aware of the things around him. 'Sensory overload'

Tony grabbed the blanket and pulled it over his head. It blocked out the light but he felt the fabric on his skin like sand paper and he was uncomfortable. He covered his ears but he heard his heartbeat like a drum.

'_This is too much._' Tony thought to himself and squeezed his eyes shut.

For awhile he sat there trying to block things out but after some time his senses regulated. Tony sighed in relief, he still felt sick from last night but not as bad as the sensory overload.

Tony stood up and almost toppled over. He grabbed the bedpost to keep himself up. Tony spotted the Spiderman suit carelessly thrown in the closet and he made his way to it. He locked the door and sat with the suit and mask.

Tony slipped on the mask and everything began to turn on. "Welcome back Peter."

"Hi... uh" '_shoot what did Peter call the AI? Something with a K.._' "-Kelly?"

"Your heart rate is abnormally fast and you seem to have my name confused. Should I enable the training wheels protocol and call Mr. Stark?" The AI asked and Tony rolled his eyes.

"Again with the Mr. Stark.." he mumbled, "No I'm not a kid, I don't need- Wait actually yes! Call him!"

"Calling Mr. Stark"

* * *

**Hello! This is the first Avengers Fan Fic I've written. I'm really excited to put this out there and continue to write all my stories!**


	2. Seal My Lips

Chapter 2

Peter opened the messages from his contact and before he could answer the texts FRIDAY cut his thoughts short.

"You have an incoming call from Peter Parker, shall I direct the call to Pepper?"

"No-"

"Yes!" Pepper interrupted from the hall.

"Directing call.." FRIDAY confirmed Peter's worst nightmare. Pepper wasn't able to see Peter make distressed hand motions.

Pepper picked up her phone and she flipped her hair over her shoulder. She leaned on the doorway and looked to Peter sitting on the bed.

"Hey Peter", Pepper answered the phone.

Tony on the other end nearly had a heart attack. "Hey.. Ms. Potts. Is Tony there?"

Pepper eyed Peter who was nervously pinching the bed sheets. "Tony's not available, he's not feeling good. Aren't you supposed to be at school?"

"I'm actually sick at home from school. I think I know what caused us to be sick and I wanted to talk to Tony about it."

Pepper hummed in thought, "So you're calling him Tony now?"

Tony almost choked on his saliva. ".. Uh.. That's what he wants me to call him."

Pepper squinted at the air and looked to Peter. She nodded to Peter and pressed a button on her phone and the Stark phone in his hand began to buzz. "Something's up with you two.. Tony, you can tell me anything, we're getting married for God's sake. I have to go now. Love you." She frowned as she walked away.

Peter sighed and threw his head back dramatically. He answered the phone and brought it to his ear. "Hello?"

"Kid, if you messed up my marriage we're going to have some issues." Tony still was on the call through the Spiderman mask.

Peter blinked in confusion and whispered into the phone. "You're not even married yet... You didn't warn me that your Arc Reactor was painful."

"Ah yes so sorry 'Doctor Parker' but I don't need to give you a play by play of how I'm feeling. How was I supposed to predict this was going to happen? I've lived with the Arc Reactor for years and I've gotten used to the pain. How are you feeling?"

"Beside the Arc Reactor... headache, dizzy, and feel like throwing up. You?"

"Same thing but I'm not used to your heightened senses so I can barely function right now."

Peter rubbed the area around the Arc Reactor edge, "There are sound proof headphones and sunglasses under the bed. I'm going to send Happy to pick you up and bring you here."

Tony laid back and covered his eyes, over the Spiderman mask, with his arm. "Your Aunt won't let me leave the house."

"Aunt May leaves for work at 8, you can sneak out."

"You talk from experience?"

"I'm proud and ashamed of it. I snuck out with good reason."

"Good reason being Spiderman?"

"Yeah..."

"You were the Friendly Neighborhood Spiderman.. while sick? You don't have to put yourself through that every day. There are police for a reason."

"Police don't always do the job. Besides the guilt gets to me if I don't go out. With great power comes great responsibility."

"Alright alright... I'm assuming that Tylenol or Advil doesn't work with your metabolism?"

Peter laughed sadly, "Sorry... sleep works a majority of the time."

Tony gave a long sigh and turned to lay on his side. "Ok... I'm going to try to sleep till 8. Make sure Happy knows when to come get me." He tugged on the trim of the Spiderman mask. "Try to avoid giving away that this happened. You know how the Avengers are.. I will never hear the end of this. Plus, I hate to mention that if S.H.I.E.L.D. finds out about this, we become a science experiment. They would want to use us or the body switching for their own benefits. So keep _my_ lips sealed. Ok?"

Peter kept his voice low, "Sure thing, Mr. Stark."

"Bye, Pete. See you in a bit. And please be careful." Tony sounded sincere but his voice was Peter's making the moment extremely weird.

"Wait.. what if I don't know what to say? They'll figure out that I'm not you." Peter panicked slightly.

"You don't have to interact with anyone if you stay in the bedroom. I can message you a few things that I would say or just tell them that you're too sick to think." Tony said while trying to control the rolling sickness in his stomach.

Peter sighed and fiddled with the phone in his hand. "Ok.. Thanks... This is so weird. What are we going to do?"

Tony hugged his stomach in pain and spoke with a stranded voice, "We'll figure that out later. Gotta go. End Call."

Tony pulled the Spiderman mask off quickly and stumbled off the bed to the nearest trash bin. Luckily Aunt May didn't hear him throwing up because Tony had just left the Spiderman suit out in the open.

After relieving himself, Tony was too exhausted to get up into bed and passed out on the ground next to the bin.

* * *

Soon after the phone call ended, Peter raced to the bathroom and threw up. He sat on the bathroom floor resting his head on the cabinets next to the toilet.

"FRIDAY? Did Pepper leave?" Peter asked with the little energy he had.

"Pepper Potts left approximately 24 minutes ago. Shall I call her for you?" Friday responded and Peter gripped the counter tightly as he pulled himself up.

"You know that's not what I want.." Peter shakily stood. "Can you call Happy?"

Peter heard it ring once till Happy picked up, "Hello?"

Peter took a deep breath and thought about what Tony would say. "Hey Happy, I need you to pick up the kid."

"Is he at school?" Happy asked. Peter stood at his full height and almost jumped out of his skin. He saw his reflection in the mirror and Tony Stark was looking back.

Peter shook his head and got back on track. "He's sick at home and it's important to make sure his Aunt doesn't know that he's leaving. His Aunt leaves at 8."

"What's going on? Are you feeling okay? You sound.. different." Happy said through the phone.

Peter combed his hair with his fingers. "I'm fine... Peter and I were exposed to something last night. It doesn't have any great effects, so bring him quickly."

Peter could hear a car start on the other end of the call. "Alright boss, I'll make it happen."

The call ended and Peter collapsed against the sink counter. He nearly threw up again and he accidentally slipped into sleep trying to hold back the sickness.

* * *

**Hey! I'm really glad that people like this story! I'll be updating weekly. :)**


	3. Show Time

Chapter 3

Tony woke up suddenly from bangs deafening him with his heightened senses.

"FRIDAY who is it?" Tony asked and reached to cover his ears.

No response.

_'Right...'_ Tony remembered the situation. He sat up and crawled to the bed after passing out on the ground. He looked under and grabbed the sound proof headphones and sunglasses that Peter mentioned.

Tony slipped them on and pulled himself up to his feet. He grabbed Peter's phone and looked at the time. '_8:12... shit_' Tony slipped the phone into Peter's pajama pants. He was too exhausted to change into clothes.

He unlocked the bedroom door and cautiously peeked his head out. He noticed that May definitely left for work. Tony used the wall to hold his weight and inch for the front door. The headphones block out the banging but the vibration went through the walls.

Tony unlocked the door and was relieved to see Happy. "Happy!" Tony shouted not knowing how loud he was but he was relieved to see him. Happy stepped forward and quickly grabbed Tony's trembling form.

"Jesus Peter, you doing ok?" Happy asked and Tony just blinked at him.

"I can't hear anything." Tony answered not able to read lips. Happy helped guide Tony to the car. Once in the car, Tony slowly took off the headphones like sounds were deadly. "Thanks Happy."

"Seriously kid, are you okay? The boss said you were exposed to something." Happy asked while turning off the radio and keeping his voice low.

"Tony? Well he was exposed to it too. I've been better." Tony answered leaning his head against the cold window.

"Did Tony talk to you about this?"

"Yeah.. he's probably not doing any better than I am." Tony thought about how Peter might be doing.

The corner of Happy's mouth turn up slightly. "Well you know Tony. He's not one to talk about anything that he thinks makes him look weak."

Tony couldn't help but shrug and smile in agreement. He pulled out Peter's phone and started to text Peter smart remarks and nicknames he uses. After feeling satisfied, the phone disappeared into the pajama pants he was still wearing.

He began to doze off during the drive.

* * *

Peter was mostly asleep but it was impossible for him to think straight. He felt so sick he couldn't sleep or be awake. He was in a state of slow motion sickness.

He wasn't even aware that there were others occupying the penthouse now.

"Tony?! Tony! Where are you?!" A voice called out and Peter's eyes opened slightly. He groaned quietly realizing he might be in a pickle.

"Tony?!" The voice got louder and Peter recognized it. Captain Freaking America.

Peter couldn't respond and his eyes closed. He panicked and he couldn't do anything at the moment.

"Tony! Are you okay?!" Peter heard his heavy footsteps come up next to him. He couldn't help but flinch when he felt his hands grab onto him. "He's breathing okay and he is reacting to my touch. Call Bruce."

'_Captain America was talking to someone? Call Bruce?_' Peter couldn't think straight. _'Who the heck was Bruce again? Oh! The smart guy. Wait-'_

Peter's face wrinkled in distress and he groaned in pain. "No- don't call-" He stopped talking to hold in a stirring sickness.

He opened his eyes and nearly screamed. There he was, Captain America... Peter had only met him as Spiderman a few times and he has never seen him out of uniform.

He looked concerned to Peter and he did his best to not look freaked out.

"Why not?" Cap asked and Peter blinked confused.

"What?"

"Why not call Bruce? I know you'd rather have Bruce look at you than an actually doctor."

Peter squinted to the America man. "If you mentioned a doctor I'm going to puke on you, Cap." '_High five Parker, that sounds like a Mr. Stark thing to say.'_

Captain America looked worried thinking he might actually go through with it.

Peter sighed and shifted his legs. "Can you help me up?" He asked quietly and Captain America (Peter can't remember his first name) grabbed his arms and pulled him up.

Peter put one hand on the sink counter and the other wrapped around his stomach. Captain continued to hold him up.

"What happened Tony?" A voice asked behind Peter. '_Oh yeah Captain America was talking to someone. But who? I can't answer questions. Not now.'_

Peter swayed and pretended to faint. It didn't take a lot of effort. '_I have to avoid questions till Tony gets here.'_

Captain America caught Peter and he felt fingers go to his neck. "Shit! Tony? Tony?!" Captain sighed, "He's fine. Call Bruce."

Peter stayed limp and allowed himself to slip into a slight state of sleep but still be aware. It was almost like sleep paralysis.

"FRIDAY? Are you able to scan Tony?" Captain suggested.

"My scans show that there is nothing wrong. A minor cold maybe but his brain waves are more concerning." FRIDAY responded and Peter was confused with what he heard.

Captain America lifted Peter off the ground. "Brain waves? I guess we have to wait till Bruce gets here. Nat, did you call?"

"Yes, I called the first time you asked. Relax. He's on the way up." 'Nat' said in a monotone voice. '_Nat? Who's Nat?_' A loopy Peter thought to himself.

Captain America placed Peter on the bed he keeps being dragged to. The damned silk sheets covered him again. Peter hated those sheets, they felt so gross against his sweaty skin.

"Steve? Natasha? What's wrong?" Peter heard another voice. '_Nat is Natasha! The Black Widow! Oh shit. Steve is Captain America! Well fuck a doodle doo. And the new voice is Bruce Banner. The. Fucking. Hulk.'_

Peter wanted to melt away and fanboy at the same time. He loved Bruce Banner's scientific studies on radiation! He couldn't think about that right now, he was freaking out. They couldn't find out he wasn't Tony.

"Pepper told us to keep an eye on Tony because he was sick and when we came up we found him passed out in the bathroom. Then he passed out again when he stood up. For some reason FRIDAY doesn't detect anything wrong." Steve filled in and Peter almost passed out with all the passing out Steve talked about. Sleep didn't sound too bad.

All of the sudden Peter remembered that Tony was on the way and now the Avengers were infiltrating the penthouse. '_Oh fuck_.'

"Sir's heart rate is elevating quickly." FRIDAY warned and Peter was upset that the AI would rat him out. Bruce came to the side of the bed next to Peter.

"Where did you find him again?" Bruce pulled the silk sheets off and Peter nearly kissed the doctor.

"The bathroom, he was throwing up and he threatened to throw up on me." Steve answered and Peter heard Bruce snicker.

"At least Tony has his sense of humor." Bruce lifted the AC/DC t-shirt. Peter shivered and twitched when he felt Bruce's fingers touch his skin. When the Arc Reactor was touched Peter gasped and grabbed the hand touching the metal.

Peter sprang up and saw Bruce looking back at him. When he sat up the shirt covered his torso. Peter let go of Bruce's hand. _'Time to put on a show.'_

"What's going on?" Peter asked and his voice was raspy, probably from throwing out.

Peter saw Captain America looking at him again. "You-" he looked confused, "you don't remember?"

"Jog my memory, would ya?" Peter tried his best to be casual but he felt so on edge.

Natasha sat on the bed next to Steve who was by his feet. "You're sick and you've been throwing up. You pass out a few minutes ago. Do you remember anything from this morning?"

Peter pretended to think and he scratched his head, "What day is it?" The others were patient with him.

"Monday" Steve answered looking worried.

"Ah no I don't remember." Peter figured it was best to avoid any questions.

All of the sudden FRIDAY comes through interrupting the questions. "Sir, Peter Parker is here like you requested. He is being transported by Happy Hogan. He is sick like you predicted."

All eyes were on him. "Uhh... I don't remember?" Peter tried to play dumb.

Steve looked confused and turned to Bruce. "Who is Peter Parker?"

Bruce stood from kneeling next to the bed. "He's Tony's intern. FRIDAY what's his symptoms?"

"He is dizzy and on the verge of passing out. That is all I'm aware of." Peter watched the doorway in panic.

Bruce touched Peter's shoulder. "What happened? He has similar symptoms!"

"I don't know!" Peter shrugged and scanned the people in the room.

Nat squinted to him, "The great Tony Stark stumped? This is a day to remember."

'_Fuck they're going to find me out.'_ Peter moved his legs off the bed and pushed himself up quickly.

Everyone started to make sounds of protest and Bruce put his hands on Peter's shoulders. "I think this is your body finally telling you, you need a break."

Peter shrugged his hands off. "I feel fine! I need to talk to Peter."

Peter managed to hold his own weight and he actually felt fine! No dizziness or nausea! He quickly shuffled out of the room trying to avoid the Avengers.

His fast pace brought him to Tony's living room where the elevator was. The elevator opened with a ding. He heart leaped out of his chest when he saw himself- no he saw Tony.

Tony was still in pajamas and he had the soundproof headphones around his neck and the dark sunglasses were hanging from his shirt.

Peter clenched his teeth and stepped forward. He saw Happy and his throat went tight. "Kid.." '_That's weird._' "Avengers inbound" whispered.

"What?! Why?" Tony whispered back.

Peter rolled his eyes and looked down the hall where the bedroom is. "Pepper tattled."

Tony sighed, "Figures.." Tony looked to Happy who had a hand on his shoulder.

Happy eyed Peter. "Peter was dizzy the whole trip and his senses are all over the place. How are you doing Tony?"

Peter resisted the urge to scratch his neck. That was a Peter thing to do. "Fine actually. But I have Avengers on my back now."

"Tony!" '_Speaking of which.._' Steve, Natasha and Bruce were catching up to Peter.

Happy stepped into the elevator trying to avoid the wrath of the Avengers. "You two take care of each other, okay?" The doors closed and Peter let his guard down for a second.

"Tony heelp." Peter hissed out quietly to Tony.

Tony looked calm but stressed. "We can't tell them. Especially Nat.. I can't help right now. I'm a nervous teen."

The acting started again.

* * *

**Tony and Peter finally met up! But now things are getting tough with the Avengers being their shadows. Hopefully you guys are enjoying so far! :)**


	4. Guilty Duo

Chapter 4

Steve, Natasha and Bruce approached Peter and Tony as they had their small reunion.

Bruce jogged forward, "Tony! You should stay in bed! And Peter let's get you checked out."

"I'm fine" The two said in unison.

Tony stepped forward taking the lead. "Oh my jeez, the Avengers!" He squealed like a 12 year ago.

Peter face palmed, "Stoopp, Kid" he put more emphasis on Kid.

Bruce tilted his head, "Peter you've met us before."

Tony smiled, "Yeah well that was when duty calls."

Peter was glaring lasers at Tony. "Peter.. time to stop talking."

Steve looked between the two. "What is he talking about?"

"Peter is Spiderman" Natasha answered with her arms crossed. Peter frowned to her. "I thought everybody knew."

Bruce raised his hand almost excited, "I knew"

Steve shook his head and pointed to 'Peter'. "Peter, Tony's intern, is Spiderman?"

Nat smirked, "Welcome to the party, Steve. You're late."

Tony figured Peter would be a nervous wreck meeting the Avengers and them finding out he was Spiderman so he really had to portray that.

Tony gave a shy wave and Peter didn't look up from his disappointed facepalm.

"So Peter what did Tony call you here for? He is having trouble remembering this morning." Bruce brought things back on track.

Tony looked to Peter and he finally dropped the facepalm to give a strained smile to Tony.

Tony turned to Bruce and the atmosphere froze from the shift in the conversation. It was tense.

Tony sighed, "Last night, I accidentally messed up Tony's experiment and whatever the reaction was got us both sick."

Bruce rubbed his stubble beard, "Experiment gone wrong?" He said to himself. "You're fine now? No other concerning symptoms that I don't know about?"

"No!" Peter and Tony answered too quickly.

Steve looked back and forth between the two and who knew that little action like that can give the guilty two so much anxiety. "You both seem fine now. Maybe it was a short amount of time of the worst of it."

Natasha stepped forward, "Peter, let's get you checked out. Tony, do you want to check the lab for more information?"

Peter eyed Tony, "Sure."

Tony pouted and gave a look to Peter, "I don't like needles..."

Bruce smiled reassuringly, "There will be no needles."

Peter smirked and patted Tony's shoulder too hard. "You got this, Champ" He pushed Tony forward to Nat and Bruce.

Tony looked back to Peter and gave a stealthy middle finger. Peter stuck out his tongue to Tony.

Tony was dragged off by Nat and Bruce to make sure he was okay. Peter was excited to go to the lab!

"You two have a nice relationship."

Peter nearly jumped out of his skin. He forget Steve was still there and probably witnessed the exchange.

Peter tensed but forced himself to drop his shoulders. He sighed to add effect.

"The kid needs me. He doesn't have much family to lean on so I'm there when he needs me." Peter looked down the hall where Tony once was.

Steve squinted his eyes in confusion and followed his blank stare. "Are you... like his Dad?"

Peter's cheeks went red in embarrassment. He had never thought about how much Tony was actually like a father figure in his life.

Peter smiled and lightly replied, "Yea...I-I mean n-not biologically! We aren't related! B-but do consider-" he cleared his throat, "...him family."

A smile spread across Steve's face. He rested a hand on Peter's shoulder and guided them to the elevator. "It's nice having him around. You seem... happier. Why didn't you introduce him to the Avengers?"

Peter couldn't help but drop his face. "I- Peter didn't think he was worthy or on the same playing field as us. He didn't think it was necessary to meet so he would come visit me when he knew I was alone. He was also worried about his secret identity because of the little family he has. He is trying to protect what he has left. But I guess today was different." Peter thought about how Tony didn't even try to hide his secret. He wasn't mad but he was actually relieved. No more secrets.

Steve walked into the open elevator with Peter and hit the button for the lab. "Well I'm glad today was different. It's interesting to know who was behind the Spiderman mask. It kind of freaks me out though that a kid is getting into dangerous situations with us."

Peter had to hold back an eye roll, '_Here we go again with the kid talk_'. "Peter has powers and a suit that I designed to keep him safe. If anything, he is the safest of all of us. He is also smart enough to know when he can't handle something alone." Peter looked to Steve for the first time. "Peter's a tough cookie."

Steve smirked, "If you're fine with it, I am too."

The pair was silent the rest of the trip to the lab. When the elevator movement stopped Peter felt nauseous but didn't let it show.

"Thanks for the escort but it's work time." Peter try to play it cool. He was still spiraling out of control because he was in the presence of Captain America. Not to mention he was also starting to feel sick again and he doesn't want Steve to drag him away from the lab.

Steve stepped out of the elevator and the doors closed. "Actually, I have to keep an eye on you. Pepper's orders... You might feel fine now but we still don't know what's wrong. Also.. I don't want to be on Pepper's bad side."

Steve walked over the couch that was left there for Tony's naps, and he was farther away from Peter. He sat with a small travel size sketchbook, he pulled out from his back pocket. "I won't bother you. Pretend I'm not here." Steve said and Peter sat in Tony's usual spot.

Holograms appeared before him and he had absolutely no clue how to use them. Sure he has seen Tony flick his fingers quickly over the holograms but Peter never used them and was feeling the pressure with Steve in the room.

"Tony?" _'I've been caught it's over...' _"Can I borrow a pencil? Sorry I promised not to bug you but I think I left it in my room." '_Oh... awkward'_

Peter shrugged, "Yea.." Peter grabbed the nearest pencil and under hand tossed it to Steve.

Steve caught it easily, "Thanks." He began to distract himself with a drawing.

Peter looked back to the holograms and continued his eternal dilemma. He raised his fingers and began typing into the floating screen.

Peter: FRIDAY? Are you able to type here?

Peter wrote onto the blank screen. He waited and nearly die because didn't want to have to talk to FRIDAY out loud in-front of Steve.

FRIDAY: Of course, Sir. What project will you be working on today?

The reply appeared underneath his question.

Peter glanced to Steve, who didn't even pay any attention to him, and looked back to the screen.

Peter: I have to tell you something.

FRIDAY: You can tell me anything.

Peter took a deep breath and prepared for the worst.

Peter: I need your help but don't freak out. I'm not Tony Stark.

* * *

**Hi :) I hope you guys are enjoying so far! Reviews what think will happen next! I'm interested in what you guys will predict. **


	5. The Padlock Holds Me Back

Chapter 5

Peter: I need your help but don't freak out. I'm not Tony Stark.

Peter tried not to physically show his panic because of Steve's presence.

FRIDAY: That would explain the abnormal brain waves. You must be Peter Parker, correct?

Peter almost smiled, '_FRIDAY is always so smart.'_

Peter: In the flesh-

Peter went to backspace at his stupid mistake but FRIDAY already beat him to it.

FRIDAY: Technically if you are Peter Parker then it would certainly notbe 'in the flesh'. But if that was a joke, good one.

There was a thumbs up png that was attached to FRIDAY's response and Peter smiled again but his mind was brought back to the situation.

Peter: Last night, I interrupted Mr. Stark's experiment and something went wrong causing us to switch bodies.

FRIDAY: I can recall conversations you've had with Ms. Potts and Happy Hogan on said experiment. Would you like me to pull up footage of those conversations and the moment the experiment went wrong?

Peter: No and no. Can you pull up the file Mr. Stark had for the experiment? He said he had the data written down and it would be easy to remake.

The file was brought up and Peter started to explore through the data.

* * *

Tony helplessly followed Nat and Bruce to his own bedroom. The state it was in made him cringe. The nightstand items were on the floor, the bed sheets were everywhere, and the bathroom had an odor.

Bruce saw Tony staring, "Tony had a rough morning." He pinched his nose, "Nat?-"

"Already on it." Natasha bravely walked into the bathroom like her nostrils weren't being assaulted. There was a flush in the room and the fan was turned on. She closed the door behind her after she came out.

Tony sat on the end of the bed and Bruce started to look through his med kit.

"Can you tell me how you are feeling? What was your morning like?" Bruce asked as he adjusted a stethoscope around his neck.

Tony rewinded his day and explained everything that happened. Of course he left out that he was Tony and parts of conversations. They had an understanding that Tony had a rough morning like Peter and that was all that mattered.

When Bruce checked his chest and heart beat with the stethoscope the realization that he didn't have an Arc Reactor in his chest almost made him cheer.

Tony suddenly felt nauseous and he dropped his head into his hands. He focused on the darkness and blocked out the world.

'_Owww my brain is meltinggg...'_ Tony thought as his senses started to go haywire.

"You okay, Peter?" Bruce asked and Tony almost forgot to respond.

Tony moved one hand away from his face. He made a thumbs up and quickly turned it upside down.

"Let's lay you down." Bruce helped Tony move backwards to lay down on the bed. Nat covered Tony with the silk sheets. Tony used to be repulsed by those sheets. They were uncomfortable and they felt gross but right now, Tony didn't mind them. They were heavy on his skin despite only being silk.

Tony grabbed the sunglasses that were still on his pajama shirt and he put him on. "FRIDAY, enable Spidey Overload Protocol."

The outside light began to be filtered out by the windows tinting black. Any lights were shut off and the air conditioning went silent. To Bruce it was scary that everything suddenly changed. Natasha simply glanced around to take in the different surroundings.

"What was that, Peter?" Bruce asked and Tony jumped at the sudden sound.

"My senses are naturally dialed in at 11 and sometimes my senses take in too much information at once and it hurts." Tony repeated what he heard Peter once tell him.

"What's it like?" Bruce asked a little too loud. Tony cringed and contemplated slipping on his headphones. Bruce saw the reaction and whispered, "Sorry."

Tony grimaced and closed his eyes. "It smells like my head is in that toilet. These sheets are crushing me. Every small light burns my eyes. And God... I can hear a conversation from some lady on the sidewalk. I can hear so many heart beats and my own is going to deafen me."

Bruce nervously looked to Natasha who actually showed some emotion. He couldn't pinpoint whether it was fear or shock.

Bruce whispered, "Get some rest." He carefully reached over and adjusted the headphones over Tony's ears.

Tony wouldn't admit it but he wasn't doing good. He had to make it seem like he had it together because Peter has suffered this before. But he wouldn't let Bruce know that.

Bruce moved to Natasha and whispered to her as if Tony could still hear them. "Maybe we should get Tony back in here. He knows more about Peter than any of us."

Nat stood up and brought out her phone. "I'll message Steve to see how things are going on that end."

Bruce rubbed his beard and glanced to 'Peter' with his sunglasses and headphones on. "He doesn't look great."

As if on command Tony grabbed his stomach on turned on his side. He groaned and his legs kicked away the silk sheets. Suddenly, Tony grabbed the bed and pulled himself to the edge. He threw up on the floor next to the bed and Bruce rushed to his side.

Before Bruce was next to Tony, he passed out and his head hung off the bed. Bruce grabbed his head and cradled him on his lap as he groaned.

Bruce snapped his head in Natasha's direction. She already had the phone to her ear.

When the phone picked up, Nat didn't have the chance to speak.

"Something's wrong! Tony just passed out!"

* * *

A few minutes ago...

Peter was sitting at the hologram screen in front of him and he was finding it hard to focus. The Arc Reactor made his skin feel like it was crawling and infected.

Not to mention, as soon as he started to go over the data he began to feel sick again. Since the elevator ride, his head was pounding and he felt a familiar sickness come up his throat but he forced it down.

Peter rested his arms on the table and he held his head. Sometimes he would glance back up to the screen but he would eventually hide his face again. Peter burped and felt himself coming close to throwing up.

_'I can't let Steve see me like this...' _Peter thought as he moved himself sideways in the chair. He decided he would go to the bathroom to relieve himself then come back to work.

Peter stood from the chair and his legs were shaking like a frightened dog in a thunderstorm. He held himself up with the table and he shot a careful look to Steve to see he was still distracted.

_'Not caught yet..._'Peter thought as he stepped teen trapped in the billionaire's body never made it to the bathroom, instead he collapsed and his head hit the ground like a bowling ball.

Peter passed out before he crumbled under his own weight.

* * *

Steve had his eyes on 'Tony' every time he would make a sudden movement. So when Tony started to drop his head in his hands every few minutes he began to get concerted.

'_Is something bothering Tony? Wait, did he eat today? If he continues to act strange I'll take him back to Bruce and force feed him.' _Steve thought and the words 'mother hen' popped up in his head. Thinking about how he has been called overprotective made him turn back to his sketch.

He was currently sketching Tony Stark but his mouth had a padlock keeping it shut. The drawing represented how guarded Tony is. Steve had literally just found out that he had an intern and that it was Spiderman. Peter is really important to Tony and the billionaire never mentioned him.

Steve drew more details on the padlock and paused his motion. '_One day, Tony, you'll open up to us.'_

All of the sudden, Steve saw Tony stand from his chair but Steve forced his eyes to stay on the sketchbook and continue his own activity. He wanted Tony to know that he was going to give him the space he needs without watching his every move.

Of course, that failed him. Tony collapsed to the ground and hit his head. Maybe if Steve saw his shaking form before, he could have caught him.

Steve jumped up from the couch and abandoned his sketchbook and run to Tony.

"Tony!" Reaching his side, he pulled Tony's head and torso off the ground. Tony's head rolled and faced Steve from pulling him up. Immediately Cap noticed a thin line of blood trailed out of his mouth.

"Tony, please wake up! Can you hear me?!" Steve shook his shoulders while still holding him up.

Nothing came from the unconscious genius but he heard something else that made him jump. The sound of Captain America's phone increased his nerves. With one arm cradling Tony's upper half, Steve fished out his phone.

The old timer never was great with technology but now was not the time to forget how to answer a phone call. After a few button mashing he raised the phone to his ear and interrupted out of worry.

"Something's wrong! Tony just passed out!"

* * *

**Hello everyone! I'm so glad that people really like this story. I have to let you guys know ahead of time that I might not post next week because I have to catch up on writing. **

**Also if you have Avengers stories recommendations please let me know! :)**


	6. Foreign Presence

Chapter 6

After the panicked phone call, Steve brought Tony back up to his penthouse and laid him down beside his intern. Bruce was checking over them and Nat was cleaning the ground where Peter threw up. Steve was grabbing them both their own trash cans in case there is more throwing up.

Steve sighed and he placed a trash can next to Tony's side of the bed. "I'm going to call Bucky to come over and make them some soup."

Bruce held a thermometer still in Peter's mouth and rested his other hand on the teen's forehead. He noticed the throw up on the collar of Peter's pajama shirt. Bruce glanced to Natasha as she finished cleaning the floors. "Can you find a clean t-shirt for Peter? I'm sure Tony won't mind."

The assassin stood with the dirty cloths and paper towels and gave a small nod in response.

Steve placed a second trash can on the other side of the bed next to Peter and watched Bruce study the thermometer. "What's the verdict doc?"

Bruce seemed at a loss as he stared at a perfectly normal temperature. "I'm no doctor Steve. But this just doesn't make sense! They are sick but there is no proof!"

Steve clenched his jaw and his eyes drifted to the trash bins. "Well we have physical proof of throwing up."

Bruce rubbed his eyes in distress. "I don't understand. Everything I've done says they are normal! Even FRIDAY said so! But it's like if you drag the two apart and they get worse!"

Steve's face wrinkled in thought, "You... might actually be onto something."

Bruce seemly forgot what he had just said, "What?"

Steve looked between the two unconscious males. "Taking the two apart makes them worse? Tony was fine as soon as Peter showed up. But when we spilt them up... they were sick again."

The scientist already dropped the thermometer in shock. "Same symptoms possibly at the same time! Did Tony throw up in the lab?"

Steve cringed, "No, but he had blood come out of his mouth."

Bruce turned his attention to Tony, "That can't be good."

Natasha walk in with a t-shirt from Tony collection. Surprisingly she picked one with a science pun on it. "Seems like I missed something. Did you guys have a realization or something?"

* * *

A few hours later

Bucky stopped by to make some soup. Somehow Steve had left out that Bucky was a good cook and now everyone was enjoying some soup.

Unfortunately Peter and Tony never woke up to eat the freshly made warm soup. Instead it was put in the refrigerator for later. The group was currently going over the possibilities of what could possibly be wrong.

Everyone was quiet in thought or silently bored. Steve was sitting with a notebook and pencil. Natasha was sitting with a threatening posture but her eyes showed hints of worry. Bucky was twirling a pocket knife and at first glance it would look threatening but after knowing him you'd know he was bored. After awhile of waiting, Bucky left. Bruce was typing on a laptop to sometimes freeze his actions to massage his temples. He could feel the other guy yelling to make an appearance. The Hulk pounded on his skull with each stressful thought.

Suddenly, movement made the group freeze. Tony stirred on the bed and moved to his side. He pushed off the sheets and continued to sleep. Bruce was the first to act and he moved his laptop to the night stand. He sat on the bed next to Tony and carefully put a hand on his forehead.

Tony jumped awake and grabbed his wrist. When their eyes met Tony relaxed and flopped back onto the bed. He went to put a hand on his chest but bumped his Arc reactor. He flinched painfully and looked back to Bruce.

"You can't scare a sleeping man." Tony said with an exhausted sigh.

"Tony... What was the last thing you remember?" The scientist asked.

Confusion spread across his face. He went to rub his forehead and felt the large lump. "I'm assuming this."

Bruce eyed Steve who was tense. "You don't actually remember?"

Tony squinted in thought. "Hmmmm nope." He moved to look around the room. "Jeez I must have missed something big."

They watched as Tony nearly jumped out of his own skin when he saw Peter in the bed next to him. He aggressively rubbed his eyes.

"You feeling ok?" Steve asked and his sketch was forgotten about.

"Uhhh.. Yes?- I mean of course. I feel great. Just.. Everything hit me like a train." The genius went silent and it was very out of character.

Bruce grabbed his laptop and went to type. "You remembered everything?"

Tony froze his movement of running his hand through his hair. His eyes displayed panic. "Umm.. yes?"

The scientist held out his laptop to Tony. "Hold this." Tony grabbed the laptop and Bruce went to looked through his medical bag. He paused his actions. "Wait Tony I thought you didn't like to be handed things? Why did you grab the laptop?"

Tony looked like he saw a ghost. He went pale and his eyes widened. He placed the laptop down like it physically hurt him. "Fuck!" Tony hid his face in his hands. His voice was muffled behind his hands. "I'm so fucking stupid."

Bruce looked to everyone in the room confused. "Um Tony you alright? It's ok to break your old habits. I'm sorry I mentioned it and that it took a head injury to break that habit."

Tony moved his legs off the bed and went to stand. "I can't do this.." The room erupted. Everyone moved to stop Tony from standing. "I'm fine! You don't have to baby me! I'm 15!"

As quick as he said that sentence everyone froze. Tony slapped his hands over his mouth.

Natasha stepped forward and spoke for the stunned crowd. "Seems like you have some explaining to do."

Tony sat dramatically and crossed his arms. "I can't." Natasha raised an eyebrow and Tony shuddered. "Fine! I'll do it! But if I tell you guys, you can't get SHIELD involved."

Bruce regained some of his composure. "Does this have to do with the experiment gone wrong?"

The billionaire nodded and bit his lip, which was unusual. He eyed Peter's sleeping body. "He's going to kill me for saying this. We promised to keep it a secret."

Steve looked between Peter and Tony. "What secret? You know you can trust us."

Bruce suddenly stood up and rubbed his temples aggressively. "He isn't Tony... I have to let the big guy out." He said with a strained voice. Bruce quickly left the room earning a concerned glance from Steve.

Steve looked to Natasha. "What does he mean?"

"Simple, Peter and Tony switched bodies."

Peter, who was trapped in Tony's body, nervously waved to the pair staring at him.

The super soldier shook his head trying to understand what he heard. "I'm sorry what? How do you know that?"

Neat sat on the bed next to Peter. "Earlier he didn't even realize he had an Arc reactor and hurt himself. Then I saw small body movements that didn't match. Also the big give away of him saying that he is 15 and taking the laptop from Bruce."

Steve looked Peter's way. "Is that true? You're Peter?"

Peter forced a smile as sweat dripped down his forehead. "Y-yea.. I'm actually surprised you figured it out before I said anything."

Natasha lifted a corner of her mouth to the kid. "I'm a spy. It's literally my job to observe people and their behaviors."

Peter's eyes glowed. "That is so cool Ms. Romanoff."

Steve nodded and gestured to Peter. "Ok now I see it. Definitely not a Stark thing to say."

Peter's demeanor changed and he looked upset. "I have to recreate the experiment to switch us back. I have finals tomorrow."

Steve scrunched his face in confusion. "You're.. you're worried about finals? You are trapped in the body of Tony Stark. A man who never takes care of himself. And finals is what worries you?"

"These finals are extremely important. They are what determine where I go to college." Peter said while standing and fidgeting with his hands.

"Woah woah." Steve put both his hands out, prepared to catch Peter. "You sure you're ok to stand? I saw you pass out last time you tried to walk."

Peter walked passed him without stumbling. "I'm fine. I promise." Peter walked over to the pitch black window. "Tony is experiencing my sensory overload and I..." his hand gripped the Arc reactor, "I feel like the thing keeping me alive is killing me. I want to pull this thing out but I won't." His hand dropped to his side.

Steve sat next to Natasha on the bed. "Bruce said something earlier that actually made some sense for this situation. He said that when you two separate you get sick again. Is there any explanation for that?"

Peter put his hand to his chin and he definitely looked like the Tony they knew. "Our bodies must be rejecting a foreign presence. The foreign presence being me in Tony's body. When we are closer together its like our bodies can feel our correct counterparts. But when we are apart... our bodies start to shut down.. We have to stay together and fix this.. Who knows how long we have till-"

"-That won't happen. I won't let it get close to that." Steve interrupted. Peter held himself and felt like throwing up.

Their attention shifted to Peter's body waking up.

* * *

**Hello! Sorry for the long wait. Imma be real I had some writer's block with this story. I got past the difficult parts to write and now it should be smooth sailing. **


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